EP0305710B1 - Electromagnetically actuated valve device - Google Patents

Abstract

2.1. Known electromagnetically actuated valve devices for controlling the connection between a hydraulic fluid source and a consumer system (inlet valve) or for controlling the pressure relief of a consumer system, have the disadvantage that they have only limited suitability for finely adjusting the consumer pressure, since they operate with a relatively large pressure drop between the inlet pressure and the consumer pressure with a large flow rate, which leads to the consumer pressure overshooting and undershooting. Other known valve devices of this type have a consumer-pressure-dependent response and therefore likewise have only limited suitability for the described purpose. The invention proposes solutions which permit fine adjustment of the consumer pressure in each consumer pressure range. <??>2.2. The invention proposes that the opening cross-section of an initial control valve, known per se, be made continuously adjustable by means of an actuating magnet, likewise known per se, having a flow- dependent movement characteristic; it is additionally proposed that the opening cross-section of a main valve, known per se, also be made continuously adjustable as a function of the flow, by coupling an initial control valve member in a fixed manner to a main valve member. <??>2.3. An advantageous area of application of the invention is for electrically controlled and/or electrically regulated motor vehicle brake systems (for example anti-lock braking systems).

Description

The invention relates to electromagnetically actuated valve devices according to the preambles of claims 1 and 3.

Such valve devices are known from DE 33 45 697 A1. This shows in the left part of the figure from the viewpoint of the viewer a valve device according to the preamble of claim 1 and in its right part a valve device according to the preamble of claim 3. A diaphragm is used as the actuator, which on its one side that from main valve member (there 29 and 36) each carries the first surface. The pilot chamber is bounded by the other side of the diaphragm, which forms the second surface of the actuator. The second area is larger than the first area. The respective membrane also carries a pilot valve member (there 26 and 9), which forms a pilot valve body with a pilot valve body connected to the armature of the respective actuating magnet, via which the pilot chamber of the valve device shown on the left with the working chamber and the pilot chamber of the valve device shown on the right the outlet chamber (there 11) connected to the outlet can be connected. Due to their arrangement on the membrane, the respective main valve members and pilot valve members are firmly coupled to one another such that a movement of the main valve member in the opening direction of the Main valve is at the same time a movement of the pilot valve member in the closing direction of the pilot valve. The actuating magnet of the valve devices is in each case a switching magnet, that is to say one whose armature is put into an end position by excitation or de-excitation. The respectively assigned pilot valve and the respectively assigned main valve therefore only know the positions "completely open" and "completely closed".

Valve devices of this type are only conditionally suitable for sensitive adjustment of the consumer pressure, since they always work at high throughput with a larger pressure drop between inlet pressure and consumer pressure when the actuating magnet is excited via the open main valve, which leads to overshoots or undershoots of the consumer pressure.

From EP-B-0 024 877 it is known to set the flow cross section of a valve (there 10, 18) with a movable valve member (there 18) sensitively by means of an actuating magnet with a constant current / stroke characteristic. This is done by shifting the valve member connected to the core of the actuating magnet, the size of which depends on the strength of the excitation current. However, this solution is practically only suitable for valves for small flow rates because of the magnet dimensions and costs that increase rapidly with the valve cross section and because of the excitation current requirement that increases with the magnet dimensions.

From DE 33 06 317 A1 it is known to control the cross section of a main valve sensitively by means of a pilot valve with a sensitively adjustable cross section. For this purpose, the pilot valve has a pilot valve member (there 34) connected to the armature of an actuating magnet with an excitation current-dependent power output (proportional magnet). The main valve includes a movable main valve member, which is arranged on an actuator (there about 14). In the closing direction of the main valve, the actuator is acted on a second surface by the pressure in a pilot control chamber (there 24) and by a spring (there 42). In the opening direction of the main valve, the actuator is acted upon by the inlet pressure on a first surface and by the consumer pressure on a third surface. The pilot chamber assigned to the second surface is connected to an inlet chamber assigned to the first surface (there about 16) via a throttle connection (there 20, 22). The pilot chamber can, on the other hand, be connected via the pilot valve to a working chamber (there about 18) assigned to the third surface of the actuator. When the pilot valve is opened by energizing the actuating magnet, an excess force in the opening direction of the main valve forms from a certain opening cross section due to the pressure drop in the pilot chamber on the actuator. This excess force acts via the spring, compressing the same on the pilot valve member and the armature of the actuating magnet and pushes them back in the closing direction of the pilot valve until there is a balance between magnetic force and excess force; ie pilot valve and main valve are coupled here by force. Given the excitation current the cross sections of the pilot valve and main valve are dependent on excess force or pressure difference. If the consumer system is closed, for example like a brake system in the actuated state, ie if it is actuated accordingly, it can be filled up to the inlet pressure, the excess force can be so great with this valve device for a given excitation current at a certain consumer pressure that the pilot valve and then, as a result of the pressure in the pilot chamber rising again, the main valve is closed. This valve device, like the valve devices mentioned at the outset, is therefore only of limited suitability for sensitive adjustment of the consumer pressure.

The invention has for its object to improve valve devices of the types mentioned with simple means so that they enable sensitive adjustment of the consumer pressure at any ratio of the consumer pressure to the inlet pressure.

This object is achieved by the invention specified in claims 1 and 3. Further developments and advantageous refinements are specified in the subclaims.

A pressure medium procurement system, a pressure medium supply or a shut-off or pressure control device arranged between these and the valve device according to the invention can be considered as the pressure medium source.

The invention also enables a sensitive adjustment of the flow rate into an open consumer system, i. H. in a consumer system with continuous (continuous) pressure medium consumption due to operation.

The invention is suitable for use with any pressure medium.

The invention can be implemented with any suitable type of design of the pilot valve, the main valve, the actuator and the arrangement of the surfaces on the actuator. The shapes of the slide valve, the seat valve and combined designs may be mentioned as examples of the valves. The actuator can be designed, for example, with a sliding seal and / or membrane seal, also in the form of a stepped piston.

For embodiments of the invention in which it cannot be avoided that the actuator exposes itself to the consumer pressure or the pressure in the outlet chamber with a third surface, the embodiments according to claims 2 and 4 offer solutions.

The embodiment according to claim 3 assumes that there is essentially atmospheric pressure in the outlet chamber. This is the case, for example, if the outlet is connected directly to the atmosphere as a pressure relief space. If, on the other hand, the pressure in the outlet chamber is at least temporarily noticeably higher, for example during pressure peaks Atmospheric pressure, it may also be advisable to optimize their function to design the embodiment according to claim 4. Examples of applications with a higher pressure in the outlet chamber are when the pressure medium in the pressure relief chamber is not released to atmospheric pressure - as is particularly common in systems with pressure media other than air - or when components causing dam pressure such as longer ones between the outlet and the pressure relief chamber released to atmospheric pressure Lines or sound insulation devices are arranged.

Under "steady stroke / current characteristic" is to be understood that at least within the working stroke of the armature of the actuating magnet, apart from the response level, hysteresis phenomena and the like, a certain stroke of the armature is assigned to each value of the excitation current. This dependency can be arbitrary: linear or progressive or degressive or mixed. If the armature is extended when the magnet is de-energized and if it is moved in the pull-in direction by excitation, if it is pulling, the stroke / current characteristic drops. If the armature is retracted with the actuating magnet de-energized and if it is moved by excitation in the direction of extension, if it is pushing, the stroke / current characteristic increases. These characteristics are used constructively e.g. B. achieved in that the armature is biased in a suitable manner by a spring. Depending on the type of stroke / current characteristic, the actuating magnet can or must be a permanent current or a working current magnet.

In the case of a valve device according to claims 2 or 4, the connection between the working chamber or outlet chamber and compensation chamber can be designed as a throttle connection. As a result, the actuator is only delayedly compensated for in a rapid pressure build-up phase with the result that the actuator itself and thus the main valve are given a tendency to close, which in turn stabilizes the function of the respective valve device.

The claims 9 to 17 describe in several stages of expansion, in particular in terms of production technology and thus inexpensive physical configurations of the invention. However, other configurations are also possible, for example with the actuator being designed as a stepped piston. It is also obvious that the main valve member and the pilot valve member together or each can form its own component.

Valve devices according to claim 1 and according to claim 3 can be assembled into a combined valve device. Such a unit then combines the pressure build-up function (inlet valve device) and the pressure release function (outlet valve device) for a consumer system in a cost-effective design and also offers the advantage of a space-saving and installation-saving design. For such a combined valve device, the configuration options described in the subclaims apply, but also any suitable other configuration option, for each one the valve devices summarized therein. The invention is explained below with reference to exemplary embodiments shown in the drawing.

The figure shows a combined valve device. This contains an electromagnetically actuated valve device (1) for controlling the connection between a pressure medium source, not shown, and a consumer system, also not shown, in the left-hand part from the perspective of the viewer, and an electromagnetically actuated valve device (12 ) to control the pressure relief of the consumer system.

A main valve (45, 46) is arranged in the valve device (1) between an inlet chamber (43) connected to the pressure medium source and a working chamber (32) connected to the consumer system. The main valve (45, 46) consists of a movable main valve member and a valve seat (45) fixed to the housing. An actuator, generally designated (42), is provided to control the movement of the main valve member.

In addition to the inlet chamber (43) and the working chamber (32), the housing contains a pilot chamber (40) and an equalizing chamber (36). The pilot chamber (40) is connected to the inlet chamber (43) via a throttle connection (34). The throttle connection (34) is dimensioned such that it is also described below in the manner described below Pilot valve (4, 5) cooperates. The compensation chamber (36) is connected to the working chamber (32) via a channel (33). The channel (33) is designed as a throttle connection.

The actuator (42) has a first surface (6), a second surface (35), a third surface (47) and a fourth surface (38).

On the first surface (6) associated with the inlet chamber (43), the actuator (42) is acted upon by the inlet pressure in the opening direction of the main valve (45, 46).

On the second surface (35) assigned to the pilot chamber (40), the actuator (42) is acted upon by the pressure in the pilot chamber (40) in the closing direction of the main valve (45, 46). On the third surface (47) assigned to the working chamber (32), the actuator (42) is acted upon by the consumer pressure in the closing direction of the main valve (45, 46).

On the fourth surface (38) assigned to the compensating chamber (36), the actuator (42) is again acted upon by the pressure in the compensating chamber (36) in the opening direction of the main valve (45, 46). This pressure is not the same as the consumer pressure in the working chamber (32) due to the design of the channel (33) as a throttle connection in a rapid pressure build-up phase; if, on the other hand, the channel (33) is not designed as a throttle connection, this pressure is always the same as the consumer pressure.

The second surface (35) is larger than the first surface (6).

For its electromagnetic actuation, the valve device (1) has an actuation magnet (3) with an armature (2) and a pilot valve (4, arranged parallel to the main valve (45, 46) with respect to the flow direction of the inlet chamber (43) - working chamber (32)) 5), via which the pilot chamber (40) can be connected to the working chamber (32). The actuating magnet (3) has a constant current / stroke characteristic. The pilot valve (4, 5) is formed by a pilot valve member and a pilot valve body (4) connected to the armature (2) of the actuating magnet (3). The main valve member and the pilot valve member are firmly coupled such that a movement of the main valve member in the opening direction of the main valve (45, 46) - directed upwards in the figure - is at the same time a movement of the pilot valve member in the closing direction of the pilot valve (4, 5).

The components mentioned above are constructed as follows.

The actuator (42) is designed as a piston consisting of two piston parts (44 and 39) arranged in series and firmly connected to one another via a shaft (41). The first surface (6) is arranged on the one piston part (44) above in the figure (bottom), and the second surface (35) is arranged on the other piston part (39) lying below in the figure (above). With this arrangement, the first surface (6) and the second surface (35) face each other. The first surface (6) is of one Valve seat (46) included, which thus defines its size and also serves as the main valve member. The third surface (47) is also arranged on the one piston part (44) (above). Since this is exposed to the consumer pressure in the closing direction of the main valve (45, 46), a force is generated on it that would disrupt the function described below. To avoid this, the fourth surface (38) is arranged on the other piston part (39) (below). For reasons also explained below, this is somewhat larger than the third surface (47). The third surface (47) surrounds a valve seat (5), which forms the pilot valve member. Since both the pilot valve member and the main valve member are arranged on the one piston part (44) in this way, their fixed coupling, as mentioned above, is given. The assignment of the surfaces (6 or 35 or 47 or 38) to the respective chamber takes place in that the respective surface delimits the respective chamber. Inside the valve seat (5) opens a channel (37) penetrating the stem (41) and a piston part (44), which is connected to the pilot chamber (40) via transverse openings (not shown) and which is open when the pilot valve (4, 5) creates the connection between the pilot chamber (40) and the working chamber (32). The other piston part (39) is axially displaceable and sealed in the housing and separates the pilot chamber (40) and the compensation chamber (36) by its seal, which is not shown. The throttle connection (34) between the pilot chamber (40) and the inlet chamber (43) is designed as a housing opening.

The actuating magnet (3) is falling Stroke / current characteristic executed. This characteristic is brought about, for example, in a manner not shown and known, by prestressing the armature (2) by means of a spring in its extension direction. The actuating magnet (3) is arranged in the figure above the actuator (42) with the armature (2) which can be drawn in upwards, ie in such a way that the armature (2) in the extended state with the pilot valve body (4) against the valve seat (5 ) and the valve seat (46) serving as the main valve member presses against or - depending on the level of the consumer pressure - in the direction of the valve seat (45) and thereby closes the pilot valve (4, 5). The force exerted by the armature (2) on the actuator (42) is just large enough to securely close the pilot valve (4, 5).

For the following functional description it is initially assumed that the actuating magnet (3) can be excited by means of an actuating device with a variable excitation current and that the consumer pressure is monitored by means of a pressure sensor, the pressure-dependent signals of the actuating device for switching on or off and / or to adjust or readjust the excitation current. Such a connection of the actuating magnet (3) is common, for example, in an electrically controlled and / or electrically regulated (for example anti-lock) motor vehicle brake system.

As long as the actuating device does not control an excitation current exceeding the response current, ie in the idle state, the armature (2) of the actuating magnet (3) remains extended and the pilot valve (4, 5) and the main valve (45, 46) are closed. Response current is the excitation current at which the armature (2) is released against the force of the spring mentioned from the extended position mentioned. The inlet pressure from the inlet chamber (43) is now present in the pilot chamber (40). On the actuator (42), as long as the inlet pressure is higher than the consumer pressure, there is an excess pressure force in the direction of closing the main valve (45, 46) due to the arrangement and sizes of the surfaces (6 or 35 or 47 or 38) , apart from any excess force of the spring biasing the armature (2) in the extension direction, the closing force of which represents. The closing force of the pilot valve (4, 5) is generated by this spring.

In the following explanations, only the function of the valve device above the response level of the actuating magnet (3) is considered.

When the actuating magnet (3) is excited, its armature (2) is drawn in by a stroke determined by the strength of the excitation current; the actuating magnet (3) is therefore used as a working current magnet. The pilot valve (4, 5) is opened by a corresponding cross-section through the pull-in stroke. As a result, pressure medium flows through the channel (37) and the pilot valve (4, 5) from the pilot chamber (40) into the working chamber (32) and thus into the consumer system. If the excitation current and thus the opening cross-section are small, just as much pressure medium can be introduced into the pilot chamber (40) via the throttle connection (34). continue to flow as through the pilot valve (4, 5) into the consumer system; the pressure in the pilot chamber is maintained and the main valve (45, 46) is closed, so that the consumer system experiences only a small pressure medium supply with a correspondingly slow increase in consumer pressure.

With a higher excitation current, the pull-in stroke of the magnet (2) and thus the opening cross-section of the pilot valve (4, 5) initially become so large that more pressure medium flows out of the pilot chamber (40) through the pilot valve (4, 5) than via the throttle connection ( 34) can flow into them. This results in a pressure drop in the pilot chamber (40) and an excess force in the opening direction of the main valve (45, 46) on the actuator (42), which is caused by movement (lifting) of the actuator (42) and thus the main valve member (valve seat 46) from the valve seat ( 45) the main valve (45, 46) opens. During this opening movement of the actuator (42) and thus of the main valve member, the valve seat (5) serving as the pilot valve member is taken along in the closing direction of the pilot valve (4, 5). The opening movement of the actuator (42) and thus the main valve member and at the same time the closing movement of the pilot valve member come to a standstill when the opening cross section of the pilot valve (4, 5) has decreased to a value which, despite the pressure medium flowing out of the pilot chamber (40 ) in the consumer system in the pilot chamber (40) can maintain a pressure that keeps the actuator (42) in equilibrium of forces. The actuator (42) assumes a floating position in which both the pilot valve (4, 5) and the main valve (45, 46) are open and the consumer system is also supplied with pressure medium over the larger cross section of the latter with a correspondingly higher throughput and faster increase in consumer pressure. The position of the floating position and thus the opening cross section of the main valve (45, 46) are determined by the pull-in stroke of the magnet (2) and thus by the excitation current. Within the scope of the operating range of the actuating magnet (3), which is defined in addition to the extended position by a stop for the armature (2) in the pull-in direction, the opening cross-section of the main valve (45, 46) and thus the pressure medium throughput in the consumer system and the consumer pressure increase -Speed of be set by the excitation current.

The increase in consumer pressure also leads to an increase in pressure in the pilot chamber (40). This, as well as the application of pressure to the third surface (47) by the consumer pressure, results in an increase in the force acting on the actuator (42) in the closing direction of the main valve (45, 46). However, this increase in force is compensated for by the fact that the increase in consumer pressure also propagates into the compensation chamber (36) and also leads to an increase in force on the fourth surface (38). The actuator (42) therefore always remains essentially in the equilibrium of forces when the main valve (45, 46) is open, so that the main valve cross-section and the pilot valve cross-section, which have been set as a function of the excitation current, remain essentially unchanged with the excitation current unchanged.

On the other hand, it has the same opening cross-sections the valves (4, 5 or 45, 46) the consumer pressure rise results in a (physically-related) degressive course (flattening) of the pressure medium throughput and thus the rate of consumer pressure rise.

• der erregerstromabhängigen Möglichkeit, nur das Vorsteuerventil (4, 5) zu öffnen,
• der erregerstromabhängigen Einstellbarkeit des Öffnungsquerschnitts des Hauptventils (40, 41) und
• des zuletzt erwähnten degressiven Verlaufs der Verbraucherdruckanstiegs-Geschwindigkeit bei steigendem Verbraucherdruck

zur Sicherstellung der erfindungsgemäß angestrebten feinfühligen Einstellung des Verbraucherdrucks über den gesamten Druckbereich geeignet.
Die Ventileinrichtung (1) ermöglicht beispielsweise, den Verbraucherdruckanstieg in mehrere Phasen mit unterschiedlichen Hauptventilquerschnitten und Verbraucherdruckanstiegs-Geschwindigkeiten aufzuteilen. So könnte in einer ersten Phase durch Erregung des Betätigungsmagneten mit einem hohen Erregerstrom ein schneller Verbraucherdruckanstieg bewirkt werden. Signalisiert der Drucksensor das Erreichen eines vorbestimmten Verbraucherdrucks, so könnte in einer oder mehreren weiteren Phasen die Betätigungseinrichtung den Erregerstrom auf Werte herabsetzen, bei denen der Soll-Verbraucherdruck in den Bereich mit degressivem Verlauf der Druckanstiegs-Geschwindigkeit fällt.The valve device (1) is because

• the excitation current-dependent possibility of only opening the pilot valve (4, 5),
• the excitation current-dependent adjustability of the opening cross section of the main valve (40, 41) and
• the last-mentioned degressive course of the rate of increase in consumer pressure with increasing consumer pressure

suitable for ensuring the sensitive setting of the consumer pressure desired according to the invention over the entire pressure range.
The valve device (1) makes it possible, for example, to divide the increase in consumer pressure into several phases with different main valve cross sections and rates of increase in consumer pressure. In a first phase, excitation of the actuating magnet with a high excitation current could result in a rapid rise in consumer pressure. If the pressure sensor signals that a predetermined consumer pressure has been reached, then in one or more further phases the actuating device could reduce the excitation current to values at which the target consumer pressure falls within the range with a degressive course of the pressure rise rate.

If the pressure sensor then signals that the target consumer pressure has been reached, a further increase in consumer pressure on the part of the actuating device is prevented by switching off the excitation current and thus closing the pilot valve (4, 5) and the main valve (45, 46) without any significant overshoot. If the consumer pressure then falls below the setpoint, the setpoint consumer pressure can be restored on the basis of the corresponding signal from the pressure sensor by opening the pilot valve (4, 5) and - depending on the speed of the consumer pressure drop - also the main valve (45, 46). The valve device (1) is therefore also suitable for sensitive tracking of dropped consumer pressure over the entire pressure range.

In the exemplary embodiment described, the fourth surface (38) of the actuator (42) is somewhat larger than its third surface (47). The resulting pressure in the opening direction of the main valve (45, 46) acts on the actuator (42) from the consumer pressure, which reduces the pressure drop in the pilot chamber (40) required to open the main valve (45, 46) and thereby a quick response of the main valve (45, 46) promotes. However, this desirable effect can be disadvantageous, in particular in the case of higher excitation currents, in that it can lead to the main valve (45, 46) tearing open and / or to unsteady movements (vibrations) of the actuator (42). For applications in which this disadvantage is intolerable, the design of the channel (33) as a throttle connection provides a remedy; this training allows the emergence in the idle state of the resulting force mentioned, but reduces it in whole or in part in the operating phase of the valve device (1) by delaying the propagation of the consumer pressure from the working chamber (32) into the compensation chamber (36).

It follows from these explanations that the valve device for normal use can also be represented as a throttle connection in the normal application even without designing the channel (33). It also emerges from these statements that the response behavior of the main valve (45, 46) can be influenced by the size relationships of the surfaces of the actuator.

In the valve device (12) shown in the right half of the figure, the main valve (19, 18) is arranged between the working chamber (32) and an outlet chamber (14), which is also provided in the housing. The outlet chamber (14) is connected to an outlet (16) and this is in communication with a pressure relief chamber.

In terms of its functional and constructive structure, the valve device (12) is the same as the valve device (1), unless stated otherwise below. your
Actuator (21)
and its components
first surface (7)
second surface (30)
third surface (13)
fourth surface (31)
a (overhead) piston part (20)
other piston part (below) (27)
Shaft (22)
Channel (29)
Main valve element (valve seat 18)
Pilot valve member (valve seat 15)
correspond to the positions of the same name (42, 6, 35, 47, 38, 44, 39, 41, 37, 46 and 5) of the valve device (1). The same statement applies to the components
fixed valve seat (19) (of the main valve 19, 18)
Pilot Chamber (24)
Compensation chamber (25)
Armature (10) (of the actuating magnet 9)
Pilot valve body (8)
Pilot valve (8, 15)
and the positions of the same name (45, 40, 36, 2, 4 and 4, 5) of the valve device (1).

The valve device (12) differs from the valve device (1) in the following properties.

The pilot chamber (24) is connected to the working chamber (32); the throttle connection (26) used for this purpose is designed as an essentially radially arranged opening in an area of the shaft (22) penetrating the working chamber (32). The first surface (7) is assigned to the working chamber (32) and accordingly subjected to the consumer pressure. The third surface (13) is the outlet chamber (14) assigned and accordingly pressurized. The third surface (13), the compensation chamber (25) and the fourth surface (31) assigned to them, as will be explained in more detail below, represent an expansion stage which expands the basic design of the valve device (12), in which the compensation chamber (25) is opposite the pressure relief chamber is sealed and connected to the outlet chamber (14) via a channel (23) shown in broken lines. In this stage of expansion, the pressure of the compensation chamber (25), which acts on the fourth surface (31), is taken from the outlet chamber (14). In the basic version, the compensation chamber (25), as characterized by an outlet (28), is connected to the pressure relief chamber.

The actuating magnet designated here (9) is arranged with respect to the actuator like the actuating magnet (3) of the valve device (1), but is designed with an increasing stroke / current characteristic. The latter is brought about, for example, by prestressing the armature (10) in its pull-in direction by means of a spring (11). When the actuating magnet (9) is de-energized, the armature (10) is fully retracted; as a result, at least the pilot valve (8, 15) is open, so that no residual pressure can build up or hold in the consumer system in this state. This is important, for example, in the case of a vehicle brake system in the released state.

If a consumer pressure is to be able to build up and hold in the consumer system and thus in the working chamber (32), the actuating magnet (9) is excited with the highest excitation current. This will make the Armature (10) fully extended and the pilot valve (8, 15) and, if opened, the main valve (19, 18) closed. The force exerted by the armature (10) on the actuator (21) is just so great that it securely closes the pilot valve (8, 15). If this state is referred to as the idle state of the valve device (12), the actuating magnet (9) thus acts in this idle state as a continuous current magnet.

If the actuating magnet (9) is de-energized, each degree of de-excitation corresponds to a stroke of the armature (10) in its retraction direction and thus an opening stroke of the pilot valve (8, 15), apart from a response de-energization caused by the closing force of the pilot valve (8, 15). . This behavior can be used for sensitive pressure relief of the consumer system. In this case and in the idle state, the valve device (12) functions analogously to the valve device (1); it can be used analogously to that and is therefore also suitable for sensitive tracking of increased consumer pressure over the entire pressure range.

If there is no significant overpressure in the outlet chamber (14), the last statements made apply to the basic version of the valve device (12), in which the third surface (13), the compensation chamber (25) and the fourth surface (31) are not are to be regarded as existing. However, if there is a significant overpressure in the outlet chamber (14) or if such a pressure occurs, it loads the actuator (21) in the closing direction of the main valve in the above-mentioned basic version via the third surface (13) (19, 18). If the overpressure in question prevails as permanent pressure, it can delay the opening of the main valve (19, 18), ie it can impair the response behavior of the valve device (12). If the excess pressure in question, for example as a dynamic pressure, occurs temporarily, it can lead to one or more unsteady movements of the actuator (21) and thus to the instable closing (fluttering) of the main valve (19, 18). An application in which an appearance of the latter type can occur is indicated by the dashed connection of a silencer (17) to the outlet (16). In these cases, the actuator (21) can be compensated for the pressure of the outlet chamber (14) completely or largely and made insensitive to it by expanding the basic design by the compensation chamber (25), the fourth surface (31) and the channel (23) . In particular, if the overpressure in question exists in the outlet chamber (14) as a permanent pressure, the channel (23) can be designed as a throttle connection in a manner not shown in a further expansion stage. As a result, analogously to the valve device (1), on the one hand the pressure acting on the fourth surface (31) is used to quickly open the main valve (19, 18), and on the other hand unsteady movements of the actuator (21) are damped or prevented.

The person skilled in the art recognizes that the actuating device mentioned in connection with the valve device (1) also takes over the control of the valve device (12) in a corresponding application and that the combined valve device shown is outstandingly suitable when these controls are linked accordingly Regulation of consumer pressure is suitable.

The person skilled in the art also recognizes that different statements made above regarding one valve device can be transferred to the other valve device in a corresponding application.

It is obvious that the scope of the invention is not limited to the exemplary embodiment described, but rather includes all configurations, the features of which are subordinate to the patent claims.

Claims (19)

1. Electromagnetically actuated valve device (1) to control the connection between a pressure medium source and a consumer installation having the features:

   a) Between an inlet chamber (43) connected to the pressure medium source, and a working chamber (32) connected to the consumer installation, there is arranged a main valve (45, 46) consisting of a valve seat (45) fixed in the housing and a movable main valve member (46);

   b) an adjusting member (42) controlling the movement of the main valve member (46) is provided;

   c) a pilot control chamber (40) is provided;

   d) the adjusting member (42) is acted on by the inlet pressure on a first surface (6), associated with the inlet chamber (43), in the opening direction of the main valve (45, 46);

   e) the adjusting member (42) is acted on by the pressure in the pilot control chamber (40) on a second surface (35), associated with the pilot control chamber (40), in the closing direction of the main valve (45, 46);

   f) the second surface (35) is larger than the first surface (6);

   g) the pilot control chamber (40) can be connected to the working chamber (32) by way of a pilot control valve (4, 5);

   h) the pilot control valve (4, 5) is formed by a movable pilot control valve member (5) and a pilot control valve body (4) which is connected to the armature (2) of the actuating magnet (3);

   i) the main valve member (46) and the pilot control valve member (5) are rigidly coupled together in such a way that a movement of the main valve member (46) in the opening direction of the main valve (45, 46) is at the same time a movement of the pilot control valve member (5) in the closing direction of the pilot control valve (4, 5),
   characterised by the features:

   j) the actuating magnet (3) has a constant current/stroke characteristic;

   k) the pilot control chamber (40) is connected to the inlet chamber (43) by way of a throttled connection (34);

   l) the throttled connection (34) is such that with a small opening cross-section of the pilot control valve (4, 5) it permits a pressure medium throughput into the pilot control chamber (40) at least as great as the pilot control valve (4, 5) from the pilot control chamber (40) and with an increasing opening cross-section of the pilot control valve (4, 5) permits a smaller pressure medium throughput into the pilot control chamber (40) than the pilot control valve (4, 5) from the pilot control chamber (40).
2. Valve device according to Claim 1, wherein the adjusting member (42) is acted on by the consumer pressure on a third surface (47), associated with the working chamber (32), characterised by the features:

   a) the third surface (47) is so arranged on the adjusting member (42) that the pressure bearing on the surface (47) acts on the adjusting member (42) in the closing direction of the main valve (45, 46);

   b) an equalization chamber (36), connected to the working chamber (32), is provided with which there is associated a fourth surface (38) of the adjusting member (42) on which the adjusting member (42) is acted on by the pressure in the equalisation chamber (38) in the opening direction of the main valve (45, 46).
3. Electromagnetically actuated valve device (12) to control the relief from pressure of a consumer installation having the features:

   a) Between a working chamber (32) connected to the consumer installation, and an outlet chamber (14) connected to an outlet (16), there is arranged a main valve (19, 18) consisting of a valve seat (19) fixed in the housing and a movable main valve member (18); the outlet (16) being at least indirectly connected to a pressure relief space;

   b) an adjusting member (21) controlling the movement of the main valve member (18) is provided;

   c) a pilot control chamber (24) is provided;

   d) the adjusting member (21) is acted on by the consumer pressure on a first surface (7), associated with the working chamber (32), in the opening direction of the main valve (19, 18);

   e) the adjusting member (21) is acted on by the pressure in the pilot control chamber (24) on a second surface (30), associated with the pilot control chamber (24), in the closing direction of the main valve (19, 18);

   f) the second surface (30) is larger than the first surface (7);

   g) the pilot control chamber (24) can be connected to the outlet chamber (14) by way of a pilot control valve (8, 15);

   h) the pilot control valve (8, 15) is formed by a movable pilot control valve member (15) and a pilot control valve body (8) which is connected to the armature (10) of the actuating magnet (9);

   i) the main valve member (18) and the pilot control valve member (15) are rigidly coupled together in such a way that a movement of the main valve member (18) in the opening direction of the main valve (19, 18) is at the same time a movement of the pilot control valve member (15) in the closing direction of the pilot control valve (8, 15),
   characterised by the features:

   j) the actuating magnet (9) has a constant current/stroke characteristic;

   k) the pilot control chamber (24) is connected to the working chamber (32) by way of a throttled connection (26);

   l) the throttled connection (26) is such that with a small opening cross-section of the pilot control valve (8, 15) it permits a pressure medium throughput into the pilot control chamber (24) at least as great as the pilot control valve (8, 15) from the pilot control chamber (24) and with an increasing opening cross-section of the pilot control valve (8, 15) permits a smaller pressure medium throughput into the pilot control chamber (24) than the pilot control valve (8, 15) from the pilot control chamber (24).
4. Valve device according to Claim 3, wherein the adjusting member (21) is acted on by the pressure in the outlet chamber (14) on a third surface (13) associated with the outlet chamber (14),
   characterised by the features:

   a) the third surface (13) is so arranged on the adjusting member (21) chat the pressure bearing on the surface (13) acts on the adjusting member (21) in the closing direction of the main valve (19, 18);

   b) an equalisation chamber (25), connected to the outlet chamber (14), is provided with which there is associated a fourth surface (31) of the adjusting member (21) on which the adjusting member (21) is acted on by the pressure in the equalisation chamber (25) in the opening direction of the main valve (19, 18).
5. Valve device according to one of Claims 1 to 4, characterised in that the actuating magnet (3) has a rising stroke/current characteristic, and so pulls.
6. Valve device according to one of Claims 1 to 4, characterised in that the actuating magnet (9) has a falling stroke/current characteristic, and so pushes.
7. Valve device according to one of Claims 2 or 5 to 6, characterised in that the connection between the working chamber (32) and the equalisation chamber (36) is in the form of a throttled connection (channel 33).
8. Valve device according to one of Claims 4 to 6, characterised in that the connection between the outlet chamber (14) and the equalisation chamber (25) is in the form of a throttled connection.
9. Valve device according to one of Claims 1 to 2 or 5 or 7, characterised by the features:

   a) The adjusting member (42) is in the form of a piston consisting of two piston parts (44) and (39) arranged in series and rigidly connected to each other by means of a shank (41);

   b) the first surface (6) is arranged on one piston part (44) and the second surface (35) on the other piston part (39), the first surface (6) and the second surface (35) facing towards each other.
10. Valve device according to Claims 2 and 9, characterised in that the third surface (47) is also arranged on one piston part (44) and the fourth surface (38) is also arranged on the other piston part (39).
11. Valve device according to one of Claims 3 to 6 or 8, characterised by the features:

    a) The adjusting member (21) is in the form of a piston consisting of two piston parts (20 and 27) arranged in series and rigidly connected to each other by means of a shank (22);

    b) the first surface (7) is arranged on one piston part (20) and the second surface (30) on the other piston part (27), the first surface (7) and the second surface (30) facing towards each other.
12. Valve device according to Claims 3 and 11, characterised in that the third surface (13) is also arranged on one piston part (19) and the fourth surface (31) is also arranged on the other piston part (27).
13. Valve device according to one of claims 9 and 10, characterised by the features:

    a) One piston part (44) including the first surface (6) serves with a valve seat (46) as the main valve member and at the same time as the pilot control valve member;

    b) the shank (41) and one piston part (44) are penetrated by a channel (37) connected to the pilot control chamber (40) and opening within the pilot control valve member (valve seat 5).
14. Valve device according to one of Claims 11 and 12, characterised by the features:

    a) One piston part (20) including the first surface (7) serves with a valve seat (18) as the main valve member and at the same time as the pilot control valve member;

    b) the shank (22) and one piston part (20) are penetrated by a channel (29) connected to the pilot control chamber (24) and opening within the pilot control valve member (valve seat 15).
15. Valve device according to Claims 2 and 13 or 4 and 14, characterised in that a valve seat (5 or 15) surrounded by the third surface (47 or 13) serves as the pilot control valve member.
16. Valve device according to one of the preceding Claims, characterised in that the throttled connection (34) between the inlet chamber (43) and the pilot control chamber (40) or between the working chamber and the pilot control chamber is in the form of an aperture in the housing.
17. Valve device according to one of claims 13 to 15, characterised in that the throttled connection (26) between the inlet chamber and the pilot control chamber or between the working chamber (32) and the pilot control chamber (24) is in the form of a substantially radially arranged aperture in a region of the shank (22) which penetrates the inlet chamber or the working chamber (32).
18. Valve device according to Claim 1 (1), characterised in that it is assembled with a valve device according to Claim 3 (12) to form a combined valve device.
19. Combined valve device according to Claim 18, characterised in that the valve device according to Claim 1 (1) is constructed according to one of Claims 2 or 5 to 7, 9, 10, 13, 15 to 18 and/or the valve device according to Claim 3 (12) is constructed according to one of Claims 4 to 6, 8, 11 to 12, 14 to 18.

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